The goal of the present proposal is to achieve a greater understanding of the role of ascending catecholamine-containing fibers in the organization of sensorimotor functions in the rat. This research is predicated on the findings (1) that destruction of catecholamine-containing fibers within the hypothalamus result in impaired motivated behabiors (e.g., feeding and aggressive behaviors) and impaired sensorimotor functions, and (2) that these sensorimotor changes are at least partly responsible for the alterations in feeding and attack. The specific objectives of the proposal are (1) to determine precisely which pathways are responsible for these effects, (2) to characterize the nature of the behavioral change produced by destruction of these fibers, and (3) to determine to what extent alterations in the rat's responsibeness to sensory stimuli can account for the changes in performance of motivated behaviors such as feeding and drinking. The present research should provide insights into the role of the hypothalamus in feeding and aggression, the function of brain catecholamines in behavior, and the neural structures responsible for the control of sensorimotor integration.